1. Field of the Invention
This invention relates generally to pressurized grease or lubrication delivery systems for heavy construction equipment, earth-moving equipment and other equipment having on-board grease reserves, as well as the ability to safely couple and uncouple the coupler while under line pressure.
2. Description of the Prior Art
Quick-coupling devices are used extensively for transferring fuels and lubricants from supply reservoirs to tanks on self-propelled heavy construction and earth-moving equipment. In addition, there is also a frequent need to couple and decouple pressurized hydraulic lines.
U.S. Pat. No. 2,625,410 to Ernest W. Crowley, titled COUPLING, discloses a quick-disconnect coupling for fluid conduits having movable poppets which close the two separate parts of the conduit to eliminate loss of pressurized or flammable fluids during connection or disconnection.
U.S. Pat. No. 2,675,829 to Carlos B. Livers, titled QUICK-DISCONNECT COUPLING WITH SELECTIVELY OPERABLE VALVE, discloses a coupling having check valves for automatically sealing hydraulic lines when the coupling is disconnected. The check valves can also be opened and closed while the coupling is connected in order to control flow of fluid through the coupling.
U.S. Pat. No. 3,129,919 to Jack M. Evans, titled VALVED QUICK COUPLER, discloses a quick coupler in which one of the separable parts has a valve which is closed when the coupler is uncoupled and opened when the two parts are coupled.
The process of transferring pressurized grease or other less viscous lubricants from a supply reservoir to a storage reservoir on board heavy construction and earth-moving equipment presently requires the depressurization of transfer lines on both the receiver side and supply nozzle side before the nozzle is coupled to the receiver. Depressurization typically involves a bleed-off of pressurized lubricant. Not only is the bleed-off process time consuming, it also results in the discharge of costly petroleum-based lubricant that is a potential environmental pollutant.
Despite the significant useful features disclosed in the prior art relating to quick-disconnect couplers, the prior art does not show a coupler having a flow valve which cannot be actuated while the coupler is in a state of disconnection, which permits connection and disconnection operations while the lines are pressurized without loss of fluid, and which has flush face mating surfaces on both male and female portions of the connector which facilitate cleaning of the mating surfaces so as to avoid contamination of the fluid after coupling occurs.